Communication adapter switching method and apparatus

Abstract

Provided is a communication adapter switching method and apparatus in a system having a plurality of communication adapters. The method includes: setting the addresses of the plurality of communication adapters equal to the address of the first of the plurality of communication adapters; setting a packet filtering mode of the communication adapters other than the first communication adapter to a mode in which all packets are accepted; and switching from one of the communication adapters to another when the one communication adapter is disconnected during communication. Accordingly, seamless handoff from the wired LAN to the wireless LAN is possible, since the TCP/IP session is maintained with the same IP address.

1 . A communication adapter switching method in a system having a plurality of communication adapters, the method comprising: 
 setting addresses of the plurality of communication adapters a same address of a first of the plurality of communication adapters;    setting a packet filtering mode of all the communication adapters other than the first communication adapter to a mode in which all packets are accepted; and    switching from one of the plurality of communication adapters to another when the one communication adapter is disconnected during communication.    
     
     
         2 . A communication adapter switching method in a system having a plurality of communication adapters, the method comprising: 
 setting a media access control (MAC) address of a wired LAN communication adapter a same MAC address of a wireless LAN communication adapter;    setting a packet filtering mode of the wired LAN communication adapter to a promiscuous mode in which all packets are accepted; and    switching from the wired LAN communication adapter to the wireless LAN communication adapter using wireless LAN information, when the wired LAN is disconnected during communication using the wired LAN communication adapter.    
     
     
         3 . The method of  claim 2 , further comprising: 
 switching from the wireless LAN communication adapter to the wired LAN communication adapter using wired LAN information, when an event is generated indicating that the wired LAN is connected during communication using the wireless LAN communication adapter.    
     
     
         4 . The method of  claim 2 , further comprising: 
 setting a packet filtering mode of the wired LAN communication adapter to a direct, multicast, or broadcast mode.    
     
     
         5 . The method of  claim 2 , further comprising: 
 mapping the wireless LAN information to a virtual adapter if the wired LAN communication adapter is disconnected.    
     
     
         6 . A communication adapter switching apparatus in a system having a plurality of communication adapters, the apparatus comprising: 
 a virtual adapter which sets the addresses of the plurality of communication adapters equal to an address of a first of the plurality of communication adapters, and setting a packet filtering mode of all the communication adapters other than the first communication adapter to a mode in which all packets can be accepted; and    a virtual protocol driver which switches from one of the plurality of communication adapters to another when the one communication adapter is disconnected during communication.    
     
     
         7 . A communication adapter switching apparatus in a system having a plurality of communication adapters, the apparatus comprising: 
 a virtual adapter which sets a MAC address of a wired LAN communication adapter equal to the MAC address of a wireless LAN communication adapter, and sets a packet filtering mode of the wired LAN communication adapter to a promiscuous mode in which all packets are accepted; and    a virtual protocol driver which switches from the wired LAN communication adapter to the wireless LAN communication adapter using wireless LAN information, when the wired LAN is disconnected during communication using the wired LAN communication adapter.    
     
     
         8 . The apparatus of  claim 7 , wherein the virtual protocol driver comprises a link state detector which provides a connection or disconnection state every time a connection or disconnection event is generated.  
     
     
         9 . The apparatus of  claim 8 , wherein the virtual protocol driver further comprises an optimal adapter selector which determines an optimal adapter for communication based on information provided by the link state detector.  
     
     
         10 . The apparatus of  claim 9 , wherein packets received from a physical adapter are unconditionally transmitted to the virtual adapter, and packets to be transmitted to the physical adapter are transmitted to the determined optimal adapter.  
     
     
         11 . A communication adapter switching method in a system having a plurality of communication adapters, the method comprising: 
 checking whether a wired LAN (Local Area Network) is connected;    generating a wireless LAN connect event if the wired LAN is connected;    updating the wireless LAN connect information; and    communicating with the wired LAN.    
     
     
         12 . The method of  claim 11 , further comprising: 
 mapping the wireless LAN information to a virtual adapter if the wired LAN is not connected;    communicating with the wireless LAN;    generating a connect event of wired LAN;    mapping information to the virtual adapter; and    communicating with the wired LAN.    
     
     
         13 . The method of  claim 11 , wherein the wired LAN is an 802.3 wired LAN.  
     
     
         14 . The method of  claim 11 , wherein the wireless LAN is an 802.11 wireless LAN.  
     
     
         15 . A method of selecting an optimal adapter, the method comprising: 
 querying the connection state;    detecting connection state information;    selecting an optimal adapter based on the connection state information; and    mapping information of selected optimal adapter.    
     
     
         16 . The method of  claim 15 , wherein the optimal adapter is the wired LAN if both an wired LAN and an wireless LAN are connected, or the one which is connected to.  
     
     
         17 . The method of  claim 16 , wherein the wired LAN is an 802.3 wired LAN.  
     
     
         18 . The method of  claim 16 , wherein the wireless LAN is an 802.11 wireless LAN.